src/codewars/kata_next_bigger_number_same_digits.py

@@ -1,22 +1,34 @@
 def next_bigger(n):
+    # get number as digits in list
     digits = [int(x) for x in list(str(n))]
 
+    # find index of pivot. return -1 if there is no pivot, meaning number is alreadig biggest
     pivot = -1
     for i in range(1, len(digits)):
-        if digits[-1] > digits[-2 * i]:
-            pivot = -2 * i
+        if digits[-i] > digits[-i - 1]:
+            pivot = -i - 1
             break
+
     if pivot == -1:
         return -1
 
+    # find the smallest digit to the right that is bigger than the pivot
     right = digits[pivot + 1 :]
-    swamp = right.index(min(right))
-    print(digits)
-    digits[pivot], digits[len(digits) - len(right) + swamp] = (
-        right[swamp],
+    swap = right.index(min([x for x in right if x > digits[pivot]]))
+
+    # swap pivot with found digit
+    digits[pivot], digits[len(digits) - len(right) + swap] = (
+        right[swap],
         digits[pivot],
     )
-    return digits
+
+    # sort right side of new swapped pivot and replace it at the end
+    right = digits[pivot + 1 :]
+    right.sort()
+    digits[pivot + 1 :] = right
+
+    # return number
+    return int("".join([str(x) for x in digits]))
 
 
-print(next_bigger(534976))
+print(next_bigger(5113455566888))

tests/codewars/test_next_bigger_number_same_digits.py

@@ -8,4 +8,8 @@ def test_next_bigger():
     assert next_bigger(2017) == 2071
     assert next_bigger(414) == 441
     assert next_bigger(144) == 414
-    assert next_bigger(84876644310) == 86013446784
+    assert next_bigger(1234567890) == 1234567908
+    assert next_bigger(59884848459853) == 59884848483559
+    assert next_bigger(7600201336) == 7600201363
+    assert next_bigger(5113455566888) == 5113455568688
+    assert next_bigger(4769560370633) == 4769560373036